202360 EHR525 Week 12 Parkinson's Disease- Part A (DG) (1 Slide).pdf

WARNING This material has been reproduced and communicated to you by or on behalf of Charles Sturt University in accordance with section 113P of the Copyright Act 1968 (Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of th...

WARNING This material has been reproduced and communicated to you by or on behalf of Charles Sturt University in accordance with section 113P of the Copyright Act 1968 (Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. Do not remove this notice School of Allied Health, Exercise and Sports Sciences 1 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 1 EHR525 EXERCISE FOR NEUROLOGICAL & MENTAL HEALTH CONDITIONS Parkinson’s Disease- Part A Presenter: Darren Gray School of Allied Health, Exercise and Sports Sciences 2 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 2 What We Will Cover ■ Describe Parkinson’s disease and it’s primary characteristics. ■ Describe prevalence statistics for Parkinson’s disease. ■ Describe the pathophysiology and risk factors for Parkinson’s disease. ■ Describe the motor and non-motor symptoms associated with Parkinson’s disease. School of Allied Health, Exercise and Sports Sciences 3 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 3 Introduction ■ Parkinson’s disease (PD): A chronic, progressive, and incurable neurological condition largely resulting from the degeneration of dopamine producing cells in the basal ganglia. ■ PD is considered a motor disorder but it also has significant nonmotor deficits affecting cognition, behaviour, and emotion. ■ PD causes major functional impairments and disability ultimately resulting in a total loss of independence and reliance on carers. School of Allied Health, Exercise and Sports Sciences 4 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 4 Parkinson’s Disease Statistics ■ PD is the second most common neurological disease in Australia after dementia. ■ Estimated to be 80,000 cases of PD in Australia with 32 new diagnoses made each day: □ Prevalence of PD is ~1% in persons > 65 years of age. □ 20% of diagnoses <50 years of age. □ 10% of diagnoses <40 years of age. ■ No major gender differences. ■ Number of cases of PD has increased by 17% in the last 6 years: □ Prevalence projected to increase to 124,000 cases by 2034 (4%/yr). School of Allied Health, Exercise and Sports Sciences 5 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 5 Parkinson’s Disease Statistics School of Allied Health, Exercise and Sports Sciences 6 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 6 Parkinson’s Disease Health System Costs In 2014 ■ Aged care: $272.5 million or $32,208 p/p in an aged care facility. ■ Medications: $70.7 million or $1,022 p/p. ■ Inpatient and outpatient hospital services: $70.6 million or $1,020 p/p. ■ GP services: $7.1 million or $103 per PWP. ■ Other AHP services: $14.6 million or $210 p/p. School of Allied Health, Exercise and Sports Sciences 7 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 7 Pathophysiology ■ Basal ganglia: A group of nuclei in the brain interconnected with the cerebral cortex, thalamus and brainstem. ■ Basal ganglia provides essential neural input needed for motor control: □ □ □ □ Timing of muscle contraction. Scaling of muscle force. Coordination of multi-joint movements. Movement sequencing. ■ Also contributes to executive function, behaviour, and emotion. School of Allied Health, Exercise and Sports Sciences 8 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 8 Basal Ganglia ■ Five (5) components of the basal ganglia: □ Striatum: • Caudate nucleus.(CN) • Putamen(Put) □ Global pallidus.(Gpi, Gpe) □ Subthalamic nucleus.(ST) □ Substantia nigra(SN) School of Allied Health, Exercise and Sports Sciences 9 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 9 Basic neural circuits of the Basal Ganglia ■ STRIATUM consists of the Caudate + Putamen.(St = C + Put) ■ Primary input site of the Basal Ganglia from the Premotor and Sensorimotor cortex. Cx > St ■ A loop sends motor signals to GLOBUS PALLIDUS, then CORTEX via THALAMUS (VL) ■ The primary role of the BG is in movement planning and modulation of motor pathways. ■ Integrates a variety of sensory and motor signals.. School of Allied Health, Exercise and Sports Sciences 10 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 10 The pathways of the BG Normal motor control Cx > Spinal Cord >> Movement Via PYRAMIDAL SYSTEM for voluntary control The BG control system to MODIFY AND FINE TUNE this OUTPUT for movement. This is achieved via DIRECT – “drive” and INDIRECT – “ brake” system. The output nuclei of the BG are Globus Pallidus (GP) interna (-) and externa (-) School of Allied Health, Exercise and Sports Sciences 11 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 11 The DIRECT pathway of the BG. A POSITIVE FEEDBACK circuit. INHIBIT> INHIBITION> = PROMOTE. GPi sends the primary inhibitory (-) output signals from the BG to motor cortex via the Thalamus. The output connection in the STRIATUM are Promoted by D1 receptors DOPAMINE from SN Cx + St – Gpi – Th + Cx School of Allied Health, Exercise and Sports Sciences 12 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 12 The INDIRECT pathway of the BG. A NEGATIVE FEEDBACK circuit. INHIBIT> INHIB> INHIBITION = INHIBITION. Gpe sends the primary inhibitory (-) output signals from the BG to the motor cortex via the Thalamus. The output connection in the STRIATUM is Promoted by D2 receptors DOPAMINE from SN Cx + St – Gpe – STN + Gpi – Th + Cx School of Allied Health, Exercise and Sports Sciences 13 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 13 Neurotransmitters in the BG GLUTAMATE – Cortical motor projects excitation to the striatum. DOPAMINE – stored in the substantia nigra and projects to the striatum. Loss of DOP from SN to striatum leads to REDUCED D1 and lowered promotion of the direct pathway and promote indirect. Note the role DOP Leading to an increase of inhibition of the the thalamo cortical projections. School of Allied Health, Exercise and Sports Sciences 14 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 14 PATHWAYS School of Allied Health, Exercise and Sports Sciences 15 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 15 Basal Ganglia Motor Circuits ■ Direct pathway: □ Involved in facilitation/excitation of WANTED movements. □ Projections from caudate/putamen  GPi/SNr  thalamus/PPN creates an overall net excitatory effect for movement. GPi/ SNr ■ Indirect pathway: □ Involved in inhibition of UNWANTED movements. □ Projections from caudate/putamen  GPe  STN  GPi/SNr  thalamus/PPN creates an overall net inhibitory effect for movement. Note these two pathways School of Allied Health, Exercise and Sports Sciences 16 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 16 Substantia Nigra ■ Made up of two (2) parts: □ Substantia nigra compacta. □ Substantia nigra reticularis. ■ Substantia nigra compacta produces dopamine and supplies it to the striatum via the nigrostriatal pathway:  Substantia nigra reticularis is also a major output nuclei to thalamus and pedunculopontine nucleus (PPN). School of Allied Health, Exercise and Sports Sciences 17 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 17 Five (5) Cortical Circuits Involving The Basal Ganglia School of Allied Health, Exercise and Sports Sciences 18 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 18 Function of Basal Ganglia in Movement Control ■ A major role of basal ganglia is to provide both inhibition and facilitation of motor pathways via secondary structures. ■ Output from BG INHIBITS: 1.Thalamus (VL)- ensures a nominal amount of activity in the Motor Cx <<Reduces unwanted activity in the CSpTracts=Pyramidal tract> 2. PPN (Pedunculopontine nucl) – which inhibits RetSpT <<Promotes PMRF and LMN>> ■ Voluntary muscles, Postural and girdle muscles and pattern generators ( walking ) School of Allied Health, Exercise and Sports Sciences 19 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 19 Basal Ganglia In Parkinson’s Disease ■ In PD, the degeneration of dopaminergic neurons of the substantia nigra pars compacta triggers a cascade of functional changes affecting the whole basal ganglia network. ■ Presence of Lewy bodies increases. School of Allied Health, Exercise and Sports Sciences 20 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 20 Effect Of PD On Basal Ganglia Motor Circuitry ■ PD disrupts direct and indirect pathways. ■ Inhibitory output from GPi and SNr is unchecked leading to excessive inhibition of the thalamus and PPN. GPi/ SNr □ Less motor cortical drive to voluntary muscles (slow movement, freezing, etc). □ Higher brainstem drive to trunk and girdle muscles (rigidity). ■ 80% loss of dopamine producing cells is needed to disrupt these pathways and cause to motor dysfunction. School of Allied Health, Exercise and Sports Sciences 21 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 21 Aetiology of Parkinson’s Disease ■ PD is idiopathic and cause remains unknown. ■ Interaction between ageing, genetics, and the environment are thought to be involved. ■ Autoimmune responses and mitochondrial dysfunction may also contribute to the disease process. School of Allied Health, Exercise and Sports Sciences 22 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 22 Risk Factors ■ PD is an idiopathic disease. ■ Combination of ageing, environmental, and genetic links are thought to play a role in disease development. ■ Risk factors include: □ □ □ □ □ Chemical exposure. Rural residence. Metal exposure. Physical inactivity. TBI. ■ Protective factors include: □ Caffeine consumption. □ Smoking. □ Anti-inflammatories. School of Allied Health, Exercise and Sports Sciences 23 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 23 Motor Symptoms ■ Cardinal motor symptoms include: □ □ □ □ Resting tremor (~4-6Hz). Bradykinesia (slowness of movement). Rigidity (muscle stiffness). Postural instability (loss of balance). ■ Other motor symptoms include: □ □ □ □ Akinesis (loss of voluntary movement). Freezing (experiencing a sudden inability to move). Stooped posture. Shuffling gait. School of Allied Health, Exercise and Sports Sciences 24 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 24 Parkinsonian Gait ■ Rigidity/bradykinesia and lose of associated movements. ■ Stooped with head and neck flexed forward, knees flexed. ■ Flexed at shoulder, elbow, and wrist with fingers extended. ■ Decreased arm swing. ■ Slow, stiff, shuffling, small steps, ■ En bloc turning. ■ Freezing of gait. Note these gait characteristics School of Allied Health, Exercise and Sports Sciences 25 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 25 Non-Motor Symptoms ■ Impaired basal ganglia function impairs other cortical loops. ■ Results in non-motor symptoms. ■ Dementia occurs in severe disease. School of Allied Health, Exercise and Sports Sciences 26 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 26 Summary ■ PD is a prevalent condition and the number of cases are predicted to increase into the future. ■ PD is characterised by motor dysfunction as a result of a loss of dopamine producing cells in the basal ganglia. ■ Cause of PD is unknown and thought to involve the interaction between ageing, genetics, and environmental factors. ■ Basal ganglia is involved in many cortical circuits and as such PD is also associated with a number of motor and non-motor symptoms that influence exercise. School of Allied Health, Exercise and Sports Sciences 27 SCHOOL OF EXERCISE SCIENCE, SPORT & HEALTH 27